android - Selecting All Items in a Listview on checkbox select

Question

I am using simple listView with simple_list_item_multiple_choice I have added a checkbox and on its checked event want all list items to get selected and on unchecked all items to get unselected.. Here is the code..

CheckBox select_all = (CheckBox) dialog.findViewById(R.id.chk_all);
        arrayAdapter = new ArrayAdapter<String>
        (ctx,android.R.layout.simple_list_item_multiple_choice,readyToDownload );
        lv.setChoiceMode(ListView.CHOICE_MODE_MULTIPLE);
        lv.setAdapter(arrayAdapter);

   select_all.setOnClickListener(new OnClickListener() {
    public void onClick(View v) {
            if(select_all.isChecked())
            {
                // check all list items
            }
            if(!select_all.isChecked())
                {
                    //  unselect all list items
                }

            }
                }); 

Answer 1

for ( int i=0; i < listview.getChildCount(); i++) {
   listview.setItemChecked(i, true);
}